Funding for this research was provided by:
Development Funding of Shaanxi Fourth People Hospital (2017SY-006)
Received: 7 November 2017
Accepted: 31 January 2018
First Online: 19 February 2018
: All experimental procedures used in this study were approved by the Animal Ethics Committee of the Shaanxi Forth People Hospital (Shaanxi, China).
: Not applicable.
: The authors declare that they have no competing interests.
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